Giant Symptomatic Rectal Mucocele following Subtotal Colectomy

INTRODUCTION: Rectal mucoceles rarely occur and only a few cases are described in the literature. They usually appear after subtotal colectomy or Hartmann procedure originating from persisting rectal mucus production and simultaneous stenosis of the anal canal. CASE PRESENTATION: A 74-year-old female patient presented with the feeling of an abdominal growing mass. Complex medical history included a subtotal colectomy with an end ileostomy and a mucous fistula at the descending colon due to Crohn disease at the age of 16 years. MRI showed a massive dilatation of the remaining colon and the rectum. Endoscopy failed due to complete anal stenosis and stenosis of the descending colon at the stoma site. A total proctocolectomy was performed. The pathology report showed a dilated rectum and sigma with large amounts of partly calcified mucus. There was no evidence of dysplasia, malignancy, or Crohn manifestation in the completely obliterated proximal colon and the anus. CONCLUSION: Our case report underlines the importance of active endoscopic surveillance of the remaining colon and rectum in patients with diverting stomas and inflammatory bowel disease in order to detect stenosis. If endoscopic control is not possible due to obliteration, surgical therapy must be discussed due to the risk of developing cancer.